A variety of fan systems have been made and used over the years in a variety of contexts. For instance, various ceiling fans are disclosed in U.S. Pat. No. 7,284,960, entitled “Fan Blades,” issued Oct. 23, 2007; U.S. Pat. No. 6,244,821, entitled “Low Speed Cooling Fan,” issued Jun. 12, 2001; and U.S. Pat. No. 6,939,108, entitled “Cooling Fan with Reinforced Blade,” issued Sep. 6, 2005. The disclosures of each of those U.S. patents are incorporated by reference herein. Additional exemplary fans are disclosed in U.S. Pub. No. 2008/0008596, entitled “Fan Blades,” published Jan. 10, 2008; U.S. Pub. No. 2009/0208333, entitled “Ceiling Fan System with Brushless Motor,” published Aug. 20, 2009; and U.S. Provisional Patent App. No. 61/175,210, entitled “Ceiling Fan with Variable Blade Pitch and Variable Speed Control,” filed May 4, 2009, the disclosures of which are also incorporated by reference herein. Alternatively, any other suitable fans may be used in conjunction with embodiments described herein.
A fan blade or airfoil may include one or more upper air fences and/or one or more lower air fences at any suitable position(s) along the length of the fan blade or airfoil. Merely exemplary air fences are described in U.S. Provisional Patent App. No. 61/248,158, entitled “Air Fence for Fan Blade,” filed Oct. 2, 2009, the disclosure of which is incorporated by reference herein. Alternatively, any other suitable type of component or feature may be positioned along the length of a fan blade or airfoil; or such components or features may simply be omitted.
The outer tip of a fan blade or airfoil may be finished by the addition of an aerodynamic tip or winglet. Merely exemplary winglets are described in U.S. Pat. No. 7,252,478, entitled “Fan Blade Modifications,” issued Aug. 7, 2007, the disclosure of which is incorporated by reference herein. Additional winglets are described in U.S. Pub. No. 2008/0014090, entitled “Cuffed Fan Blade Modifications,” published Jan. 17, 2008, filed Sep. 25, 2007, the disclosure of which is incorporated by reference herein. Still other exemplary winglets are described in U.S. Design Pat. No. D587,799, entitled “Winglet for a Fan Blade,” issued Mar. 3, 2009, the disclosure of which is incorporated by reference herein. In some settings, such winglets may interrupt the outward flow of air at the tip of a fan blade, redirecting the flow to cause the air to pass over the fan blade in a perpendicular direction, and also ensuring that the entire air stream exits over the trailing edge of the fan blade and reducing tip vortex formation. In some settings, this may result in increased efficiency in operation in the region of the tip of the fan blade. In other variations, an angled extension may be added to a fan blade or airfoil, such as the angled airfoil extensions described in U.S. Pub. No. 2008/0213097, entitled “Angled Airfoil Extension for Fan Blade,” published Sep. 4, 2008, the disclosure of which is incorporated by reference herein. Other suitable structures that may be associated with an outer tip of an airfoil or fan blade will be apparent to those of ordinary skill in the art. Alternatively, the outer tip of an airfoil or fan blade may be simply closed (e.g., with a cap or otherwise, etc.), or may lack any similar structure at all.
The interface of a fan blade and a fan hub may also be provided in a variety of ways. For instance, an interface component is described in U.S. Pub. No. 2009/0081045, entitled “Aerodynamic Interface Component for Fan Blade,” published Mar. 26, 2009, the disclosure of which is incorporated by reference herein. Alternatively, the interface of a fan blade and a fan hub may include any other component or components, or may lack any similar structure at all.
Fans may also include a variety of mounting structures. For instance, a fan mounting structure is disclosed in U.S. Pub. No. 2009/0072108, entitled “Ceiling Fan with Angled Mounting,” published Mar. 19, 2009, the disclosure of which is incorporated herein. In addition, a fan may include sensors or other features that are used to control, at least in part, operation of a fan system. For instance, such fan systems are disclosed in U.S. Pub. No. 2009/0097975, entitled “Ceiling Fan with Concentric Stationary Tube and Power-Down Features,” published Apr. 16, 2009, the disclosure of which is incorporated by reference herein; U.S. Pub. No. 2009/0162197, entitled “Automatic Control System and Method to Minimize Oscillation in Ceiling Fans,” published Jun. 25, 2009, the disclosure of which is incorporated by reference herein; and WIPO Pub. No. WO/2009/100052, entitled “Automatic Control System for Ceiling Fan Based on Temperature Differentials,” published Aug. 13, 2009, the disclosure of which is incorporated by reference herein. Alternatively, any other suitable mounting structures and/or fan systems may be used in conjunction with embodiments described herein.
Some fans may include blades that are formed as a unitary construction. By way of example only, a fan blade may be entirely formed as an extrusion of aluminum or other material. Alternatively, fan blades may be unitarily formed using a variety of other techniques and/or materials, including combinations thereof. In some settings, it may be desirable to provide a fan blade formed of different components, some of which may be formed of material(s) that differ from material(s) of which other components of the fan blade are formed. For instance, it may be desirable in some settings to provide modular fan blade components that permit various fan blades to be modified with relative ease. By way of example only, in some settings, differing components of a fan blade may be configured to reduce the total weight of the fan blade; provide a soft leading edge for the fan blade (e.g., for durability, safety, and/or other purposes); permit tailoring of the aerodynamics of the fan blade to specific applications by interchanging leading and/or trailing edge components; permit tailoring the aerodynamics along the length of a fan blade by combining shorter segments of leading or trailing edge components of different designs in a single assembly; provide different colors within a fan blade (e.g., for visibility, aesthetics, and/or other purposes); and/or provide transparent or translucent segments within a fan blade (e.g., to contain lighting, for visibility, for aesthetics, and/or for other purposes). Of course, differing components of a fan blade may be configured and used for a variety of other purposes, in addition to or in lieu of any of the merely illustrative examples noted above.
While a variety of fans and fan systems have been made and used, it is believed that no one prior to the inventors has made or used a fan system as described herein.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.